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Density dependent spin polarisation in ultra low-disorder quantum wires

D. J. Reilly·T. M. Buehler·J. L. O'Brien·A. R. Hamilton·A. S. Dzurak·R. G. Clark·B. E. Kane·L. N. Pfeiffer·K. W. West
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Abstract

There is controversy as to whether a one-dimensional (1D) electron gas can spin polarise in the absence of a magnetic field. Together with a simple model, we present conductance measurements on ultra low-disorder quantum wires supportive of a spin polarisation at B=0. A spin energy gap is indicated by the presence of a feature in the range 0.5 - 0.7 X 2e^2/h in conductance data. Importantly, it appears that the spin gap is not static but a function of the electron density. Data obtained using a bias spectroscopy technique are consistent with the spin gap widening further as the Fermi-level is increased.

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D. J. Reilly, T. M. Buehler, J. L. O'Brien, A. R. Hamilton, A. S. Dzurak, R. G. Clark, B. E. Kane, L. N. Pfeiffer, K. W. West. 2002-02-19. Density dependent spin polarisation in ultra low-disorder quantum wires. https://doi.org/10.1103/physrevlett.89.246801

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